TREASURE ISLAND — A trio of beach hoteliers say parking rows of cars for events on a wide stretch of sand behind their properties isn’t just hurting their businesses, it’s against state law.

If city leaders don’t curtail festivals that bring vehicles onto the beach, such as a Rotary Club carnival in the spring, the hoteliers’ attorney has vowed to sue.

A state law passed in the 1980s prohibits driving on Florida beaches except for maintenance, unless local governments already had allowed it, attorney Tyler Cathey wrote in a letter to Treasure Island City Attorney Maura Kiefer.

Pinellas County makes no such allowance, and Treasure Island only amended its beach driving ordinance in 2003, which means it runs afoul of the state law, he wrote.

“The cumulative effect of promoting and holding events that allow driving and parking on the beach evidences a lack of proper management by the City of Treasure Island, violating the direct Legislative mandate in Florida’s Constitution,” wrote Cathey, who represents owners of Page Terrace Motel, Windjammer Resort Hotel and Thunderbird Beach Resort.

Kiefer replied that her staff was investigating whether the law applies to public property where cars “park or traverse for limited deliveries.”

Many business owners have praised the city for bringing dozens of new events to the beach in the past decade, drawing tourists at nonpeak times for spectacles like the Sanding Ovations sand-sculpture competition in November.

These beach festivals strain the city’s limited parking capacity, though, and a particularly broad section of public beach at the end of 107th Avenue has become an auxiliary parking area for some of them.

The Rotary Club’s Greatest Show on Surf, a four-day carnival with a Ferris wheel, music and other attractions, pushed Page Terrace Motel owner Arthur Czysczon and the other hoteliers over the edge.

The carnival happened at peak season, in March, and many of Czysczon’s guests were not pleased to have their views of the beach and Gulf of Mexico obstructed by rides.

The city has held more than 50 events with beach parking since 2010, Cathey stated in his letter to the city.

That’s a good thing, local chamber of commerce leaders say.

“We know all the visitors yearly that call in, they want to plan their vacations around these events. And some of the events we’ve had are amazing,” said Jo Massaro, head of the combined Treasure Island and Madeira Beach chamber.

Massaro said the fight against beach parking is championed by a small minority; most businesses have embraced the events.

Kiefer, in her letter, points out that Thunderbird owner David King is sponsoring the Fall Fly at T.I. kite event this month, which has participants anchoring sport kites to vehicles on the beach.

The aggrieved hotel owners aren’t against all beach events, Czysczon said, as long as they’re not disruptive to their guests.

Of course, should the threatened lawsuit come to fruition, it might preclude several events on Treasure Island’s calendar, Vice Mayor Alan Bildz said.

“If the hotels’ attorneys are right about parking on the beach, then, yes, it would affect a lot,” said Bildz, who has been a lone voice in support of the affected hotels at past city commission meetings.

Few of Florida’s beaches allow cars, with the exception of Daytona Beach and some adjacent beach communities, where driving has been a long-standing tradition.

Private property owners and environmentalists, who have voiced concerns about sea turtle nests, have filed lawsuits in the past decades to limit driving there.

Czysczon said he has collected thousands of online and paper petitions from local residents and hotel guests who want to see beach parking banned.

“We support the events that incorporate sand, ocean and wind. These are nature’s events — events that should be on the beach,” he said.